This invention relates to wind machines.
In one class of wind machine, each of a plurality of blades is independently mounted about its own axle for rotation about its axle and each are mounted to a central rotating shaft about which they orbit. A tail vane controls the orientation of the blades about their independent axles so that they are always at an angle which receives the benefit of the prevailing wind direction as they orbit about the central axis. The main shaft is rotated by the blades as they orbit and provides a mechanical output or drives an electrical generator for an electrical output.
In a prior art wind turbine of this class, the speed control of the windmill is centrifugally governed and the blades are relatively heavy. The main shaft, if it is used to drive an electrical generator, drives a DC generator or an AC generator through a transmission. A typical wind turbine of this class is disclosed in U.S. Pat. No. 715,480 granted Dec. 9, 1902 although others are known in the art.
The prior art wind turbines have several disadvantages, such as: (1) they are not sufficiently strong and durable; (2) they have a high capital cost for each kilowatt of power provided; (3) their speed control is load dependent rather than dependent upon wind velocity; (4) they are damaged or must be completely shut down at high velocities of wind; and (5) either asynchronous low-frequency AC potential is provided or DC potential or AC synchronous potential at a very low power because of inefficient coupling or the need of DC-to-AC conversion.